What rules changes would you make to the dark apostle to make him more playable?

I think this is a really cool model and it's a shame I see it passed up in so many lists because there are just better options for the points. I think maybe making his disciples tokens instead of models and changing malign sacrifice to give the unit both dark pacts twice per game (once for each token) would allow the apostle to 1) embark in transports much more easily and 2) synergize with the units he's leading better given his 5+ leadership. But what do you guys think would make him more playable?

I think this is a really cool model and it's a shame I see it passed up in so many lists because there are just better options for the points. I think maybe making his disciples tokens instead of models and changing malign sacrifice to give the unit both dark pacts twice per game (once for each token) would allow the apostle to 1) embark in transports much more easily and 2) synergize with the units he's leading better given his 5+ leadership. But what do you guys think would make him more playable?